On the 14-day Jewels of the Arctic cruise operated by Aurora Expeditions, for example, passengers on the Polar Pioneer had access to a naturalist, geologist, an assistant expedition leader and Miller, an expedition leader who has spent 14 seasons in the Arctic and 20 in the Antarctic.

BBC: Life in the fragile, frozen Arctic

He tags along on a 1960s expedition to Greenland and saves the day when the group runs out of food, by felling a polar bear with a single shot.

FORBES: Don't Go Near The Volcano